diff --git a/lib/_emerge/EbuildMetadataPhase.py b/lib/_emerge/EbuildMetadataPhase.py
index 54177840c7..524a8507b7 100644
--- a/lib/_emerge/EbuildMetadataPhase.py
+++ b/lib/_emerge/EbuildMetadataPhase.py
@@ -36,6 +36,7 @@ class EbuildMetadataPhase(SubProcess):
         "repo_path",
         "settings",
         "deallocate_config",
+        "portage_ebuild_extra_source",
         "write_auxdb",
     ) + (
         "_eapi",
@@ -165,6 +166,9 @@ def _async_start_done(self, future):
             self.cancel()
             self._was_cancelled()
 
+        self.portage_ebuild_extra_source = self.settings.get(
+            "PORTAGE_EBUILD_EXTRA_SOURCE"
+        )
         if self.deallocate_config is not None and not self.deallocate_config.done():
             self.deallocate_config.set_result(self.settings)
 
@@ -191,6 +195,8 @@ def _unregister(self):
         if self._files is not None:
             self.scheduler.remove_reader(self._files.ebuild)
         SubProcess._unregister(self)
+        if self.portage_ebuild_extra_source:
+            os.unlink(self.portage_ebuild_extra_source)
 
     def _async_waitpid_cb(self, *args, **kwargs):
         """
diff --git a/lib/portage/package/ebuild/doebuild.py b/lib/portage/package/ebuild/doebuild.py
index c4780a6ff8..4486909667 100644
--- a/lib/portage/package/ebuild/doebuild.py
+++ b/lib/portage/package/ebuild/doebuild.py
@@ -2197,10 +2197,19 @@ def spawn(
         env = orig_env.copy()
 
         t = env["T"]
-        if not os.path.isdir(t):
-            os.makedirs(t)
+        if os.path.isdir(t):
+            ebuild_extra_source_path = os.path.join(t, ".portage-ebuild-extra-source")
+        else:
+            ebuild_extra_source_fd, ebuild_extra_source_path = tempfile.mkstemp(
+                prefix="portage-ebuild-extra-source-",
+            )
+            os.chmod(
+                ebuild_extra_source_path, stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH
+            )
+            os.close(ebuild_extra_source_fd)
+            # The file will be deleted by EbuildMetadataPhase._unregister()
+            mysettings["PORTAGE_EBUILD_EXTRA_SOURCE"] = ebuild_extra_source_path
 
-        ebuild_extra_source_path = os.path.join(t, ".portage-ebuild-extra-source")
         with open(ebuild_extra_source_path, mode="w") as f:
             for var_name in unexported_env_vars:
                 var_value = orig_env.get(var_name)